Voidblessed Sorcerer

Instants and Sorceries you cast cost
{u}{b} less to cast. (this ability only
reduces the amount of coloured mana
needed to cast instant and sorcery spells.)
"At Ahriman's command, the exalted
sorcerers gave their lives and psychic energy
away to the cause, and succeeded in opening
a gateway into the webway."